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The Bishop's Palace, Kirkwall is a 12th-century palace built at the same time as the adjacent St Magnus Cathedral in the centre of Kirkwall. It housed the cathedral's first bishop, William the Old of the Norwegian Catholic Church who took his authority from the Archbishop of Nidaros (Trondheim). The ruined structure now looks like a small castle.
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In the United Kingdom, a scheduled monument is a 'nationally important' archaeological site or historic building, given protection against unauthorised change.
There are about 20,000 scheduled monuments in England representing about 37,000 heritage assets. Of the tens of thousands of scheduled monuments in the UK, most are inconspicuous archaeological sites, but some are large ruins.
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